With enactment of the SOX Act, companies are being required to strengthen security measures to bring their operations into compliance with this law. Security management has become important even for the client terminals used by individuals in a company, and there is an increasing need for constant awareness and monitoring of the latest security situation regarding client terminals (simply referred to as client hereinafter) connected to a network.
Conventional techniques for meeting this need, for example, include a method for auditing the security situation of a network-connected client disclosed in Japanese Patent Application Laid-open No. 2007-66265 (referred to as Patent Document 1). Also, software for checking whether or not the assets (installed software and patches) of each client connected to a network are secure, totaling the results of the check and notifying the administrator have been released by various vendors.
Meanwhile, from the standpoint of reducing TCO and improving operations management, virtualization technology, which uses software to emulate a computer, thereby providing a virtual computer environment, that is, a virtual machine, has come into widespread use. Utilizing virtualization technology makes it possible to share a machine image of a virtual machine between a plurality of virtual machines. In accordance with this, only the difference data between the shared machine images needs to be managed for each virtual machine.
Virtualization technology such as this, for example, is disclosed in Patent Document 1 and Japanese Patent Application Laid-open No. 2006-221649 (called Patent Document 2 hereinafter), and, various vendors have also released products that make use of this virtualization technology, such as Linked Clone technology by VMware (registered trademark) (refer to the VMware (registered trademark) View 3 brochure (called Non-Patent Document 1 hereinafter)), and FlexClone (registered trademark) technology by NetApp (registered trademark) (refer to the NetApp (registered trademark) FlexClone (registered trademark) Datasheet (referred to as Non-Patent Document 2 hereinafter)). Further, technology for migrating a virtual machine from one physical machine to another physical machine, for example, has also been disclosed in Japanese Patent Application Laid-open No. 2007-66265.
In a large-scale network environment, the number of clients targeted by a security check is enormous, and therefore carrying out a security check of all the clients requires a long period of time, making it difficult to grasp the latest security situation of each client.
Further, the increase in the number of virtual machines in line with the spread of virtualization technology in recent years is expected to significantly increase the number of management-targeted clients, most likely making it increasingly difficult in the future to discern the latest security situation of each virtual machine in a large-scale network environment. For this reason, security checks of network environments like this will have to be carried out faster.